Can insert into membranes and form chloride ion channels. Channel activity depends on the pH. Membrane insertion seems to be redox-regulated and may occur only under oxydizing conditions. Involved in regulation of the cell cycle. {ECO:0000269|PubMed:10834939, ECO:0000269|PubMed:11195932, ECO:0000269|PubMed:11551966, ECO:0000269|PubMed:11940526, ECO:0000269|PubMed:11978800, ECO:0000269|PubMed:14613939, ECO:0000269|PubMed:9139710}.

Subunit:

Monomer. Homodimer (in vitro). Interacts with TRAPPC2. Dimerization requires a conformation change that leads to the exposure of a large hydrophobic surface. In vivo, this may lead to membrane insertion. Interacts with AKAP9. {ECO:0000269|PubMed:11551966, ECO:0000269|PubMed:12163479, ECO:0000269|PubMed:12681486, ECO:0000269|PubMed:14613939}.

Subcellular location:

Nucleus. Nucleus membrane {ECO:0000305}; Single-pass membrane protein {ECO:0000305}. Cytoplasm. Cell membrane {ECO:0000305}; Single-pass membrane protein {ECO:0000305}. Note=Mostly in the nucleus including in the nuclear membrane. Small amount in the cytoplasm and the plasma membrane. Exists both as soluble cytoplasmic protein and as membrane protein with probably a single transmembrane domain.

Members of this family may change from a globular, soluble state to a state where the N-terminal domain is inserted into the membrane and functions as chloride channel. A conformation change of the N-terminal domain is thought to expose hydrophobic surfaces that trigger membrane insertion. {ECO:0000269|PubMed:14613939, ECO:0000269|PubMed:18850721}.

Ptm:

Hydrogen peroxide treatment causes a conformation change, leading to dimerization and formation of an intramolecular disulfide bond between Cys-24 and Cys-59.

Miscellaneous:

The protein seems to have very low affinity for glutathione, even though glutathione binding was observed in protein crystals.